Investigating the effects of aerosol optical properties, meteorology and morphology on radiative forcing and climate change

Abstract

The presence of aerosol has a significant impact on radiation and cloud formation. Aerosol radiative forcing denotes the imbalance in the Earth's radiation budget induced by human-generated aerosol. Despite substantial progress in monitoring, interpreting and modeling these processes over the last four decades, considerable uncertainties persist. This paper examines several crucial factors, such as aerosol optical properties and composition, contributing to a novel perspective on aerosol radiative forcing and heating rates throughout the industrial era. The estimation of forcing and heating rates over urban industrial areas aims to discern the specific contribution of industrial aerosol. The constraints on our understanding of aerosol absorbance and the factors influencing trends in ground radiative fluxes limit the assessment of forcing from aerosol–radiation interactions. Disturbances in radiative equilibrium prompt the evolution of the system's state, and human activities, by altering atmospheric chemistry, can potentially induce such disturbances. Raipur, the state capital of Chhattisgarh, is selected as the study area located in the eastern central portion of India. AOD, AE and SSA values were retrieved from satellite and model-derived data using OMI and MERRA-2. RF estimation was performed using COART model. The annual mean value of RF during 2016–2021 is found to be 10.92 W/m² with 11.85 W/m², 11.03 W/m², 10.51 W/m² and 10.29 W/m² during autumn, winter, spring and summer, respectively. RF is found to be dependent on SSA. Heating rate in the study area is found to be 0.328 K/day, indicating strong localized warming. This is significantly higher than typical tropospheric or stratospheric heating rates in the study region, indicating contribution from anthropogenic sources and a potential for atmospheric instability. This work studies the regional effect of optical properties radiative forcing studying the meteorological and morphological properties on air quality.